You Googled it didn't you?
Yep - you got it.

Some other stats from the article.

The NAS is supporting 60 million aircraft per year at more than 19,000 airports across the nation. I don't know what criteria they are using to count the airports. I've not seen a count on the actual number of "airfields" in the US, but I flew an approach to one in the Texas panhandle a few weeks ago that looked to be abandoned!

USMCFLYR